Severe Weather 3-24-24 and 3-25-24

[cheese007]

SPC has put out a D5 15% contour with hints at more unsettled weather in the following days

ZCZC SPCSWOD48 ALL
   ACUS48 KWNS 200900
   SPC AC 200900

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0400 AM CDT Wed Mar 20 2024

   Valid 231200Z - 281200Z

   ...DISCUSSION...
   Medium-range models suggest that blocking centered over the
   northeastern Pacific will break down this weekend, as a more
   progressive regime shifts across the central into eastern
   mid-latitude Pacific, and gradually inland through much of the U.S.
   by the middle to latter portion of next week.  Initially, flow
   downstream of the weakening blocking may undergo amplification,
   including mid-level troughing offshore of the southern Atlantic
   Seaboard, and larger-scale mid-level troughing progressing inland of
   the U.S. Pacific coast through the Great Plains and Mississippi
   Valley through early next week.  

   Within the inland advancing troughing, there appears reasonable
   agreement between the ECENS/ECMWF, GEFS and GFS model output that a
   significant lead short wave perturbation will accelerate
   northeastward out of the Southwest across the southern Rockies late
   Sunday into Sunday night.  As this occurs, a rather deep cyclone is
   forecast to continue to form to the lee of the Front Range during
   the day, before migrating southeastward then eastward into the
   adjacent high plains.  Although it still appears that low-level
   moisture return in the wake of prior low-level drying and cooling
   across the northern Gulf Basin may still be on the margins for
   vigorous thunderstorms, the development of steep
   lower/mid-tropospheric lapse rates may compensate.  Coupled with
   potentially intense wind fields and strong forcing for ascent,
   organized severe thunderstorm development seems probable late Sunday
   afternoon into Sunday night.  This may include supercells initially,
   then an evolving narrow squall line.

   Into the early through middle portion of next week, uncertainties
   concerning a subsequent short wave emerging from the Southwest
   increase.  However, it appears probable that there will be at least
   narrow corridors of strong to severe thunderstorm development on
   following days across the southeastern Great Plains into lower
   Mississippi Valley and perhaps parts of the Southeast.

   ..Kerr.. 03/20/2024

   CLICK TO GET WUUS48 PTSD48 PRODUCT

[cheese007]

D5 15% contour added covering much of AR/LA/MS as well as the MO bootheel, far western TN, and a smidge of east TX

[METALSTORM]

Seems like Sunday could be an opportunity for dryline chasers. A good preseason game to get the equipment ready. 

[Ed, snow and hurricane fan]

Sunday looks more like a day for chasing hail and structures.  Surface based CAPE is fairly low, surface CINH is fairly high.  Maybe W. Oklahoma might see a tornado or two, if I had to guess..  Impressive ML lapse rates though, and there is enough plenty of shear.  Looking at Day 2 area HRRR and 3 and 12 km NAM, a squall line with gusty winds seems more likely judging my simulated radar, although there is some surface based instability and a lot of low level shear.  Maybe embedded in a line, or a cell ahead of the main line.

[Ed, snow and hurricane fan]

Not hatched for large hail, but enhanced risk for hail probs >30% w/i 25 miles for a small part of N Central Oklahoma and S central Kansas on updated SWODY1

[Chinook]

There have been a couple of confirmed tornadoes today. One confirmed tornado right now is near Oakley Kansas. This is a pretty low-moisture situation today. Apparently even up to 1000 J/kg of surface based CAPE near this area in Kansas. I don't even really know if a lot of hail will happen today/tonight.

 

Quote

The National Weather Service in Goodland has issued a

* Tornado Warning

* Until 545 PM CDT.

* At 508 PM CDT, a confirmed tornado was located 5 miles west of
  Grinnell, moving northeast at 25 mph.

  HAZARD...Damaging tornado.

  SOURCE...Law enforcement confirmed tornado.

 

[Chinook]

Here's a non-confirmed tornado warning that developed out of a pretty good supercell that's been going on near Wichita Falls TX

[cheese007]

D2 ENH with Sigtor hatch

SPC AC 241723

   Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1223 PM CDT Sun Mar 24 2024

   Valid 251200Z - 261200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
   OF THE LOWER MISSISSIPPI VALLEY...

   ...SUMMARY...
   Severe thunderstorms with a threat for a few tornadoes and damaging
   winds are possible Monday through Monday night from parts of east
   Texas through the Lower Mississippi Valley.

   ...Synopsis...
   Deep upper troughing is forecast to be in place across the central
   CONUS early Monday morning. Several shortwave troughs will be
   embedded within this large parent upper troughing, including one
   over the Mid MO Valley and another over the southern High Plains. 
   The northern shortwave is forecast to continue northward through the
   Upper MS Valley while the southern shortwave moves quickly
   northeastward across eastern OK/northeast TX and into the Mid MS
   Valley. Evolution of these shortwaves, in particularly the southern
   High Plains shortwave, will induce a more negative tilt to the
   parent upper trough as the entire system gradually shifts eastward.

   The surface pattern early Monday morning will be complicated by an
   ongoing convective line across TX, but the general expectation is
   for a low to be over central KS with the primary cold front
   extending southwest from this low across the TX Panhandle into
   northeast NM. A secondary cold front/dry line will also extend
   southward from this low across central OK and north TX into the TX
   Hill Country. Showers and thunderstorms will likely be ongoing along
   an outflow boundary preceding this secondary cold front/dry line
   from southwest MO through western AR and northeast TX. The cold
   fronts and convective line are all forecast to progress eastward
   throughout the day, with some intensification of the convective line
   possible as it interacts with the greater low-level moisture over
   the Lower MS Valley. Thunderstorm development is also expected
   farther north across western IA as the primary surface low moves
   through during the afternoon.

   ...Mid-South into the Lower MS Valley...
   Favorable low-level moisture will exist ahead on the convective line
   expected to be ongoing early Monday from southwest MO through
   northeast TX, contributing to modest buoyancy despite widespread
   cloud cover and relatively cool surface temperatures. Generally
   modest convection will likely be ongoing within this line early
   Monday, but the expectation is for the line to reintensify during
   the early afternoon as large-scale forcing increases, the cold front
   catches up to the line, and buoyancy reaches its diurnal max. This
   reintensification will likely begin near the TX/LA border, with
   storms reaching their maximum intensity across far southeast AR,
   eastern LA, and western MS.

   Very impressive wind fields are anticipated across the region, with
   southeasterly surface winds ahead of the line contributing to large,
   looping low-level hodographs. Additionally, very strong
   southwesterly mid-level flow will support a southwesterly deep-layer
   shear vector with a notable line-perpendicular orientation.
   Consequently, there is likely a risk for a robust, forward
   propagating line capable of both strong gusts and embedded QLCS
   tornadoes. Also, given that the line is expected to be fairly weak
   at the beginning of the period, there is some chance for more
   discrete updrafts as the reintensification of the line begins,
   particularly with southern extent. The airmass will become less
   unstable with eastward extent into AL, and the expectation is for
   the overall intensity of the line to weaken as it moves into AL
   overnight.

    ...Western Iowa/Far Northwest MO and Vicinity...
   Within the larger-scale upper trough over the central states, an
   embedded, cold-core mid-level shortwave trough will move quickly
   northeastward across the Upper Midwest Monday. Most guidance still
   shows low 50s surface dewpoints present near a deep surface low
   across western IA and vicinity Monday afternoon. Given the cold
   mid-level temperatures, only modest daytime heating is needed for
   airmass destabilization. Deep-layer shear appears strong enough for
   a few organized thunderstorms and isolated/marginally severe hail
   and strong/gusty winds may occur with any sustained low-topped
   convection.

   ..Mosier.. 03/24/2024